Some types of bicycles, such as racing style bicycles, have their handlebars positioned level with or below their seats and forward of the front steering spindle so that when a rider leans forward into a horizontal position the handlebars are easily gripped by the hands of the rider. Although this horizontal position reduces wind resistance and is preferred for racing, many riders using bicycles for general transportation or for more casual recreational bicycle riding prefer to sit in an upright position. However, the relatively low and forward position of the racing style handlebars prevents riders from riding the bicycles in the upright position or at least renders such riding uncomfortable while steering the bicycles. Yet racing style bicycles are otherwise desirable for general transportation or casual recreational riding because of their popularity as well as their light weight and efficient operation.
The prior art, as exemplified in U.S. Pat. No. 263,293 and U.S. Pat. Nos. 3,760,648, 3,803,937 and 4,361,057, includes various techniques such as upper handlebar extensions and pivoting handlebars for enabling bicycles with racing style handlebars to be ridden in the more comfortable upright sitting position. The U.S. Pat. No. 263,293, in particular, shows an auxiliary bar for attachment to a racing type bicycle handlebar including a continuous generally inverted U-shaped member with its lower ends mounted in a cantilever manner by clamps on respective left and right outer portions of the handlebar. The inverted U-shaped member is bent to form vertical support posts extending upward from clamps, a pair of horizontal portions extending rearward from the support posts to or past the steering spindle, and a crossbar joining the rear ends of the rearward extending portions. Forward and rearward forces exerted on this cantilever mounted auxiliary bar during normal steering produce rotative forces on the primary handlebar about a horizontal axis to cause increased tendency for horizontal rotation within the gooseneck clamp; such rotation can cause loss of control, resulting in an accident and injury to the rider. Furthermore, the cantilever mounting of this auxiliary bar requires generally large strong clamps and strong tubular bar material to withstand the cantilever forces at the junctions between the vertical support posts and the clamps resulting in a more expensive handlebar system.